Distributed power control with limited message passing for nonconcave utility maximization

Transmit power control in wireless networks has long been recognized as an effective mechanism to mitigate co-channel interference. The optimal transmit power control problem is typically non-convex if a system utility is to be maximized. In our recent work [1], we proposed a distributed algorithm, referred to as GLAD, that obtains the global optimal solution to the non-convex power control problem. Same as other existing distributed power control algorithms, GLAD requires extensive message passing among all users in the network, which leads to high signaling overhead and high processing complexity. To reduce the message passing, this paper proposes a variant of the GLAD algorithm, referred to as I-GLAD, where the prefix "I" stands for infrequent message passing. The convergence of I-GLAD can be proved regardless of the reduction in the message passing rate. To further reduce the processing complexity at each transmitter, we develop an enhanced version of I-GLAD, referred to as NI-GLAD, where only the control messages from the neighboring links are processed. Our simulation results show that I-GLAD approximately converges to the global optimal solution regardless of the type of the system utility function. Meanwhile, the optimality of the solution obtained by NI-GLAD depends on the selection of the neighborhood size.